1. Field of the Invention
The present invention relates to an imaging lens, an optical apparatus equipped with the imaging lens and a method for manufacturing the imaging lens.
2. Related Background Art
A zoom lens having a first lens group with negative refractive power suitable for wide-angle photography and having a vibration reduction function has been proposed, for example, Japanese Patent Application Laid-Open No. 7-152002.
With making a third lens group having negative refractive power as a vibration reduction lens group, the zoom lens has excellent vibration reduction performance. Moreover, in recent years, increased strictness about ghost images and flare defined as one of factors, which affect not only aberration correction performance but also optical performance, has been requested to such a zoom lens. Therefore, a request for the higher performance is given also to an antireflection coating formed on a lens surface, and a multi-layered film design technique and a multi-layered film forming technique continue their developments (refer to, e.g., Japanese Patent Application Laid-Open No. 2000-356704).
However, in such a zoom lens, an imaging lens having higher optical performance capable of taking a wide-angle photograph has been requested. In particular, higher optical performance has been requested to a large aperture, wide-angle zoom lens. Moreover, there has been a problem that optical surfaces of such a zoom lens tend to generate reflection light producing ghost images and flare.